Precision zeroed small-arms transmitter (ZSAT) with shooter sight-picture compensation capability

ABSTRACT

A system for precisely calibrating the misalignment of a weapon-mounted zeroed small arms transmitter (ZSAT) laser beam axis with the shooter line-of-sight (LOS) to a target in a weapon training system. When a blank cartridge is fired through a blank fire adapter (BFA) affixed to the weapon muzzle in a predetermined disposition, the dynamic muzzle displacement during the first milliseconds may be characterized as a two-dimensional shooter-independent “signature” representative of the BFA disposition, the blank cartridge and the weapon. The misalignment of the ZSAT laser beam axis with the shooter LOS is calibrated by transmitting a sequence of optical pixel signals during an early portion of the dynamic muzzle displacement interval to paint a target. A shooter LOS offset is deduced from the number of pixel signals illuminating the target and stored to compensate for any misalignment of the ZSAT laser beam axis with the shooter LOS during later use.

CROSS-REFERENCES TO RELATED APPLICATIONS

[0001] This application is related by common inventorship and subjectmatter to the commonly-assigned U.S. Pat. No. 6,406,298 entitled “LowCost Laser Small Arms Transmitter And Method of Aligning The Same,”which is entirely incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates generally to military training equipmentand more particularly to a zeroed small arms transmitter (ZSAT) assemblywith a self-aligning sight-picture compensator for offsetting themisalignment of the ZSAT laser beam axis with the shooter line-of-sight(LOS) to the target.

[0004] 2. Description of the Related Art

[0005] The Multiple Integrated Laser Engagement System (MILES 2000®)produced by Cubic Defense Systems, Inc., exemplifies a modern realisticforce-on-force training system. As a standard for direct-fire tacticalengagement simulation, MILES 2000 is a system employed for trainingsoldiers by the U.S. Army, Marine Corps and Air Force and internationalforces such as the Royal Netherlands Marine Corps, Kuwait Land Forcesand the UK Ministry of Defence.

[0006] MILES 2000 components include wearable systems for individualsoldiers and marines as well as interface devices for combat vehicles(including pyrotechnic devices), personnel carriers, antitank weapons,and pop-up and stand-alone targets The MILES 2000 laser-based systemallows troops to fire infrared “bullets” from the same weapons andvehicles that they would use in actual combat. These simulateddirect-fire events produce realistic audio/visual effects andcasualties, identified as a “hit,” “miss” or “kill.” The events are thenrecorded, replayed and analyzed in detail during After Action Reviews,which give commanders and participants an opportunity to review theirperformance during the training exercise. Unique player ID codes andGlobal Positioning System (GPS) technology ensure accurate datacollection, including casualty assessments and participant positioning.

[0007] The MILES 2000 individual weapons system includes small,lightweight components mounted on either a vest or H-harness; and aSmall Arms Transmitter (SAT) mounted on the soldier's individual weaponor machine gun, which may be appreciated with reference to thecommonly-assigned U.S. Pat. No. 5,475,385 issued to Parikh et al. andincorporated herein by reference. Realism is enhanced by employing lightwearable equipment that is nearly transparent to the user, particularlythe H-harness or vest that may be worn over other combat equipment. Thesystem replicates the ranges and lethality of the soldier's individualweapon or machine gun while holding shooter alignment during blank fire;thereby training the shooter under conditions identical to actual combatweapons operation. Thus, among other demanding technical requirements,MILES 2000 requires the SAT laser beam axis to be properly aligned withthe line of sight (LOS) axis of the weapon to ensure its rangeeffectiveness.

[0008] Disadvantageously, simply aligning the laser beam axis with theweapon LOS is not sufficient for realistic training because the opticalbeam travels instantly to the target in a straight line, which does notrepresent the parabolic trajectory of a live projectile fired from thesame weapon by the same shooter under the same circumstances. Theparabolic trajectory is aligned with the weapon sights during a formaliron-sight alignment (“zeroing”) procedure, which is in the U.S.generally required semi-annually by the military forces for each weapon.This procedure is performed at a shooting range with live ammunition bythe shooter to whom the weapon is assigned. During the typical weaponzeroing procedure, the shooter aligns the “iron” sights of the assignedweapon so that 70-80% of the shots strike targets at 25 meters (and 300meters) distance when the shooter line-of-sight (LOS) is on-target.After firing, the location of the cluster of bullet holes in the targetis observed and corresponding azimuth and elevation adjustments are madeto the conventional “iron” sights of the weapon. Live ammunition isagain fired and the process iterated until satisfactory results obtain.A record is made of the sight adjustments and attached to the weapon foruse in resetting a disturbed adjustment. The conventional sights of theM16A2 rifle may be adjusted to achieve a 95% kill ratio at both 25 and300 meters because the bullet trajectory is a flat parabola that risesto the bulls-eye at 25 meters, continues rising to a peak, and falls tothe bulls-eye at 300 meters, provided that the bulls-eyes are collinearwith the shooter LOS. Disadvantageously, this formal zeroing procedurerequires access to a live ammunition facility after the boresightingprocedure has aligned the weapon boresight to the shooter LOS.

[0009] The SAT to LOS alignment problem is well-known in the art andsolutions have been proposed by other practitioners. For example, thepresent state of the art may be appreciated with reference to thecommonly-assigned U.S. Pat. No. 5,410,815 issued to Parikh et al. andincorporated herein by reference. Parikh et al. describe an alignmentsystem that requires the weapon-mounted SAT to be clamped in anAutomatic Small Arms Alignment Fixture (ASAAF) after the shooter aimsthe weapon along a LOS to a target. Once clamped in the position forwhich the shooter LOS is aligned with the target, the ASAAF iterativelytriggers the SAT and mechanically rotates two optical wedges in the SATlaser beam axis to orient the optical beam until it is aligned along anaxis coincident with the LOS at the target. Disadvantageously, thisapproach requires many additional moving mechanical and optical partsthat increase the SAT cost and complexity and reduce its reliability.Moreover, this is a time-consuming procedure requiring the ASAAF to beshared among forty or more soldiers and the procedure may not always beperformed because it is not formally required as part of true combatdoctrine. Advantageously, alignment of the SAT laser beam with theshooter LOS instead of the weapon boresight avoids any requirement forzeroing the weapon with live ammunition during training. The SAT to LOSalignment is also customized for the individual weapon and shooter, solong as the weapon-mounted SAT retains its mechanical alignment and theweapon remains with the shooter for whom it was aligned.

[0010] But the LOS is unique to the shooter. This is because eachshooter aligns the iron sights in a fashion that is subtly unique to theindividual shooter, who may view the target “sight picture” along a LOSdescribed by the iron-sight elements in a subtly different manner fromthe LOS sighted by another shooter. Although the shooter may bepermitted to keep a personally-zeroed weapon, if the weapon is assignedto another shooter during training, it must be again zeroed by the newshooter because effective training of the shooter requires the SATassembly laser beam to be aligned with the particular LOS that the newshooter actually aligns with the target, herein denominated the “shootersight picture.” There are many nations where the same weapon is sharedamong several “citizen” soldiers during training. Unless the weapon canbe zeroed by the new shooter in a live-fire facility, the only way toprovide the proper training experience is to somehow compensate for thedifference in sight-pictures between the original and new shooters,herein denominated “sight-picture compensation.”

[0011] Other practitioners have proposed systems that provide usefulautomatic alignment compensation for military small arms trainingpurposes. For example, in U.S. Pat. No. 4,781,593, Birge et al. describea laser weapon simulator that requires a gunner to correctly lead amoving target when using a laser direct fire weapon simulator formarkmanship training. The weapon simulator includes one or more lasersfor firing a plurality of radiation beams along the weapon boresight andon one or both sides thereof An encoding circuit assigns a code to eachradiation beam and a simulated target has a radiation detector fordetecting the radiation beams of the lasers and includes a decoder forrecognizing each code assigned to each radiation beam and comparing thelead taken by the gunner with the required lead. But Birge et al neitherconsider nor suggest a solution to the sight picture compensationproblem discussed above.

[0012] In another example, U.S. Pat. No. 4,959,016 issued to Lawrencedescribes a weapon simulator for simulating small arms that includes alaser projector for attachment to the weapon. Firing the weaponinitiates the production of a narrow, pulsed, beam by the laser, andthis beam is scanned vertically downwardly while its pulse repetitionfrequency is varied as a function of vertical scan angle. The beam isreceived by a spatially diverse pair of detectors on the target. Onedetector effectively determines the width of the beam, thus permittingthe range from the weapon to the target to be computed from the beamwidth and the change in the pulse repetition frequency detected from thestart to the finish of the first detector illumination. The elevationangle of the weapon with respect to the target is computed from the meanpulse repetition frequency detected by a second detector. Finally, theaccuracy of aim of the weapon (i.e. whether the firing resulted in a hitor a miss) is determined from a combination of the range, the weaponelevation angle, and the weapon/ammunition type. But Lawrence neitherconsiders nor suggests a solution to the sight picture compensationproblem discussed above.

[0013] The above-cited U.S. Pat. No. 6,406,298 discloses a low-cost SATthat includes a hollow housing for the laser diode, the rear segment ofwhich may be permanently bent to align the laser beam with the boresightof the weapon. This advantageously permits boresight alignment of theSAT without complex optical wedges and equipment and, if the weapon isalso zeroed at 25 meters, the laser beam is then aligned with theshooter LOS without any sight-picture compensation. But any changes intarget distance from the 25/300 meter standards (for example, to 75meters) or any change in shooter introduces misalignment of the SATlaser beam and shooter LOS in the weapon. This requires some form ofsight-picture compensation in the field to provide an effective trainingexperience to the shooter. Nothing in the present art can provide thenecessary compensation, except returning to the live fire range to zerothe iron sights to accommodate the new shooter and returning to theOptical Alignment Fixture to adjust the laser beam boresight alignmentto accommodate the new target distance. Such measures must be repeatedto accommodate each change in targeting distance and shooter. Unless aweapon is properly boresighted and zeroed for the shooter and thedesired target range, sight-picture compensation is necessary for aproper training experience.

[0014] There is accordingly a clearly-felt need in the art for a shootersight-picture compensation system that can be integrated with theexisting MILES 2000 in the training field without additional expensiveand complex equipment. In particular, a compensation system is neededthat relies on existing MILES 2000 field hardware and permitsself-alignment of a zeroed SAT for another individual shooter in thetraining field whenever desired. To ensure effective training, asight-picture alignment system is requires that customizes shootersight-picture compensation for both the individual weapon and theindividual shooter. These unresolved problems and deficiencies areclearly felt in the art and are solved by this invention in the mannerdescribed below.

SUMMARY OF THE INVENTION

[0015] This invention solves the above problem by adding elements ofthis invention to the existing Zeroed Small Arms Transmitter (ZSAT)assembly, or the Multiple Integrated Laser Engagement System (MILES) SATthat has been zeroed, to permit for the first time the automaticcompensation of the shooter sight-picture without external testequipment. This invention arose in part from the unexpectedlyadvantageous observation that the dynamic muzzle displacement of aweapon during the first milliseconds is repeatable from shooter toshooter when a blank cartridge is fired through a blank fire adapter(BFA) affixed to the weapon muzzle in a predetermined angulardisposition. The dynamic muzzle displacement during the firstmilliseconds after firing a blank cartridge through the BFA may bemeasured using, for example, high-speed video photography, and may becharacterized as a two-dimensional laser-beam “dynamic muzzledisplacement signature” in azimuth (AZ), elevation (EL) and time (T).This displacement signature is determined only by the BFA dispositionand the shooter-independent characteristics of the weapon and the blankcartridge.

[0016] The term “calibration pixel” is used herein to denominate anoptical signal representing a discrete angular position in a continuousdynamic muzzle displacement signature. A “pixel” may be embodied as, forexample, a pulse-coded sequential beam number or a time-coded opticalsignal corresponding to a two-dimensional angle in AZ and EL. Thedynamic muzzle displacement signature may be expressed, for example, asa time series (with fixed or variable time interval) of two-dimensional(AZ, EL) calibration pixels referenced to the initial SAT laser beamaxis position (0,0), wherein each calibration pixel represents theangular position (AZ, EL) of the SAT laser beam at some time T aftertrigger pull.

[0017] This invention is a system and method for calibrating the shootersight-picture offset and is also a method for employing the same systemto compensate for the shooter offset during training exercises.According to this invention, any misalignment of the SAT laser beam axiswith the shooter LOS is quickly calibrated by transmitting a codedsequence of optical pixel signals during a known portion of the dynamicmuzzle displacement interval to represent the (AZ, EL, T) parameters foreach of several calibration pixels. From the number and identity of thecalibration pixel signals found to illuminate the target, ashooter-dependent LOS offset is deduced and stored. During latertraining exercises where the same weapon is used by the same shooter,this stored LOS offset is used in compensating for the target effects ofany misalignment of the SAT laser beam axis with the shooter LOS.

[0018] The same calibration pixel signals are transmitted during latersimulated fire. From the number and identity of the calibration pixelsignals found to illuminate the target, as adjusted according to thestored LOS offset, the targeting effects of the misalignment of the SATlaser beam axis with the shooter LOS are cancelled. The availablemisalignment compensation is limited to the two-dimensional (AZ, EL)region illuminated by the SAT laser beam because at least some of thecalibration pixel signals must illuminate the target bulls-eye duringuse.

[0019] It is a purpose of this invention to provide a system forautomatically calibrating a misalignment of the laser beam axis with theshooter-dependent LOS by simply firing a blank cartridge while aiming ata target in the field.

[0020] It is another purpose of this invention to provide a system forautomatically compensating for the shooter sight picture by calibratinga misalignment of the laser beam axis with the shooter LOS in twodimensions on a zeroed weapon.

[0021] In one aspect, the invention is a method for calibrating amisalignment of the laser beam axis with the shooter LOS in a weapontraining system for simulating the use of a weapon against a target by ashooter having a LOS to the target, the system including aretroreflector adapted to be secured to the target for reflecting anincident optical signal back along the line of incidence, and a SATassembly having a laser beam axis and adapted to be secured to theweapon, including the steps of (a) aligning the shooter LOS with theretroreflector, (b) triggering the weapon to fire a blank cartridge; (c)transmitting a sequence of optical pixel signals along the laser beamaxis responsive to the weapon triggering step, (d) counting the numberof optical pixel signals reflected from the retroreflector, and (e)storing a shooter LOS offset corresponding to the number of reflectedoptical pixel signals counted.

[0022] In another aspect, the invention is a weapon training system forsimulating the use of a weapon against a target by a shooter having aLOS to the target, including a first optical detector adapted to besecured to the target for receiving an incident optical signal, a firstcounter coupled to the first optical detector for counting a number ofoptical pixel signals received at the first optical detector, and a SATassembly having a laser beam axis and adapted to be secured to theweapon and having an optical transmitter and a sight-picture compensatorfor offsetting the misalignment of the laser beam axis with the shooterLOS to the target, including a controller coupled to the opticaltransmitter for producing an optical pixel signal sequence responsive tothe triggering of the weapon and a data store coupled to the controllerfor storing a shooter LOS offset corresponding to the number of opticalpixel signals counted.

[0023] In yet another aspect, the invention is a weapon training systemfor simulating the use of a weapon against a target by a shooter havinga LOS to the target, including a retroreflector adapted to be secured tothe target for reflecting an incident optical signal back along the lineof incidence and a SAT assembly having a laser beam axis and adapted tobe secured to the weapon, including an optical transmitter, an opticaldetector, and a sight-picture compensator for calibrating themisalignment of the laser beam axis with the shooter LOS, including acontroller coupled to the optical transmitter for producing an opticalpixel sequence responsive to the triggering of the weapon, a countercoupled to the optical detector for counting the number of reflectedoptical pixel signals received at the optical detector from theretroreflector, and a data store coupled to the counter for storing ashooter LOS offset corresponding to the number of reflected opticalpixel signals counted.

[0024] In another aspect, the invention is a SAT assembly having a laserbeam axis and adapted to be secured to a weapon for use in a weapontraining system for simulating the use of the weapon against a target bya shooter having a LOS to the target and including a retroreflectorsecured to the target for reflecting an incident optical signal backalong the line of incidence, the SAT assembly including an opticaltransmitter, an optical detector, and a sight-picture compensator forcalibrating the misalignment of the laser beam axis with the shooterLOS, including a controller coupled to the optical transmitter forproducing an optical pixel signal sequence responsive to the triggeringof the weapon, a counter coupled to the optical detector for countingthe number of reflected optical pixel signals received at the opticaldetector from the retroreflector, and a data store for storing a shooterLOS offset corresponding to the number of reflected optical pixelsignals counted.

[0025] In yet another aspect, the invention is a method for preciselylocating a simulated hit point on the target having a retroreflectorincluding the steps of aligning the shooter LOS with the retroreflector,triggering the weapon to fire a blank cartridge, transmitting a sequenceof optical pixel signals along the laser beam axis responsive to theweapon triggering step, counting a number of optical pixel signalsreflected from the retroreflector, and determining the simulated hitpoint corresponding to the number of reflected optical pixel signalscounted.

[0026] The foregoing, together with other objects, features andadvantages of this invention, can be better appreciated with referenceto the following specification, claims and the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] For a more complete understanding of this invention, reference isnow made to the following detailed description of the embodiments asillustrated in the accompanying drawing, in which like referencedesignations represent like features throughout the several views andwherein:

[0028]FIG. 1 is a sketch illustrating the Zeroed Small Arms Transmitter(ZSAT) system of this invention for calibrating the misalignment of theZSAT laser beam axis with the shooter line-of-sight (LOS);

[0029]FIG. 2 is a sketch illustrating the ZSAT and weapon details ofFIG. 1;

[0030]FIG. 3 is a sketch illustrating the shooter sight line, projectiletrajectory line and ZSAT laser beam axis details of FIG. 1;

[0031]FIG. 4 is a block diagram illustrating an exemplary embodiment ofthe ZSAT assembly portion of the ZSAT calibration system of thisinvention;

[0032]FIG. 5 a block diagram illustrating an alternative embodiment ofthe target portion of the ZSAT calibration system of this invention;

[0033]FIG. 6 is a sketch illustrating another alternative embodiment ofthe target portion of the ZSAT calibration system of this invention;

[0034]FIG. 7 is a sketch illustrating yet another alternative embodimentof the target portion of the ZSAT calibration system of this invention;

[0035]FIG. 8 is a chart illustrating an exemplary two-dimensionaldynamic muzzle displacement signature characterizing a weapon uponfiring a blank cartridge through a Blank Fire Adaptor (BFA) affixed tothe weapon muzzle, according to the teachings of this invention;

[0036]FIG. 9 is a chart illustrating the first quarter-cycle of theexemplary dynamic muzzle displacement signature of FIG. 8 showing anexemplary embodiment of the predetermined two-dimensional pixel sequenceof this invention;

[0037]FIG. 10 is a chart illustrating the horizontal pixel components ofthe dynamic muzzle displacement signature of FIG. 8 versus time aftertrigger pull;

[0038]FIG. 11 is a block diagram of a flow chart illustrating theautomatic sight picture alignment method of this invention; and

[0039] FIGS. 12A-12D are charts illustrating an exemplary embodiment ofthe method of this invention for deducing the horizontal component of ashooter LOS offset from the number and identity of thetarget-illuminating optical pixel signals.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0040] FIGS. 1-3 illustrate various elements of the Zeroed Small ArmsTransmitter (ZSAT) system 20 of this invention for calibrating anymisalignment of the laser beam axis 22 of the ZSAT assembly 24 with theline-of-sight (LOS) 36 of a shooter 26. Such misalignment usually existsin a zeroed weapon that has not been re-zeroed by a new shooter. ZSATassembly 24 is affixed to the weapon 28, which is aimed by shooter 26along the LOS 36 to the target bulls-eye 30. FIG. 2 shows ZSAT assembly24 affixed to weapon 28 in more detail. Weapon 28 includes a rear sight32 and a forward sight 34, both of which are aligned along LOS 36 byshooter 26. As seen more clearly in FIG. 3, shooter LOS 36 isdistinguished from laser beam axis 22 and from the boresight axis of themuzzle 38 to which a blank fire adapter (BFA) 40 is affixedsubstantially as shown. LOS 36 and axis 22 are also distinguished fromtrajectory 42 (FIG. 1) of a live projectile fired from muzzle 38, whichdescribes a parabola aligned at one end with the boresight axis ofmuzzle 38. As illustrated in FIG. 1, when LOS 36 is aligned with thecollinear bulls-eyes 30A-30B, sights 32-34 are said to be properly“zeroed” (at 25 and 300 meters) for shooter 26 when live projectiletrajectory 42 rises to the bulls-eye 30A at 25 meters, continues to apeak, and then falls to the collinear bulls-eye 30B at 300 meters asillustrated. In accordance with this invention, the targeting effects ofany misalignment of laser beam axis 22 with shooter LOS 36 in a weaponmay be automatically compensated without mechanical adjustment to anyelements of the system.

[0041]FIG. 4 is a block diagram illustrating the ZSAT calibration system44 of this invention in an embodiment adapted for use with ZSAT assembly24 (FIGS. 1-3). The optical transmitter 46 may be embodied as, forexample, an infrared (IR) laser with a wavelength in the region fromgenerally 800 nanometers to generally 10,600 nanometers and preferablyclose to 1540 nanometers. The 1540 nanometer signal wavelength ispreferred because it is eye-safe even at twenty times the necessarypower levels and pulse rates and has lower absorption and scatteringloss in smoke and haze than at 904 nm. The encoder 48 is coupled tooptical transmitter 46 for encoding the sequence of optical (AZ, EL)pixel signals transmitted along axis 22 under the control of acontroller 50. A trigger-pull sensor 52 passes a signal to controller 50that the shooter has pulled the weapon trigger (perhaps firing a blankcartridge to initiate the calibration procedure). The pixel signals maybe encoded in one dimension only (AZ, for example), in two dimensions(AZ and EL, for example), or sequentially along the dynamic muzzledisplacement signature, for example.

[0042] In one embodiment of this invention, all elements of calibrationsystem 44 are collocated in the ZSAT assembly 24 affixed to weapon 28(FIGS. 1-3), including the LOS offset logic 54, which includes anoptical sensor 56 for receiving optical pulses 57 reflected from aretroreflector disposed at target bulls-eye 30 (FIGS. 1 and 3). Anysuitable retroreflector known in the art is employed at the target toimplement the calibration procedure of this invention. For example, oneof the line of Tech Spec™ Corner Cube Retroreflectors (Trihedral Prisms)available from Edmond Industrial Optics, Barrington, N.J. is suitablefor this purpose. Optical sensor 56 sends a signal representing areceived optical pulse to the counter logic 58 and the decoder logic 60,both of which are coupled to controller 50 and operate to recover ashooter LOS offset in accordance with this invention. Decoder logic 60decodes the received pulses to identify the pixel signals, which areaccumulated by counter logic 58 and passed to controller 50, whichstores the pixel count number in a data store 62 for later use inperforming shooter sight picture compensation. Decoder logic 60 also mayoperate to recover any optical pulse coding that may have been createdby encoder 48 at transmission and this coding is passed to controller 50for use in identifying individual pixel signals to support alternativeembodiments of the sight picture compensation method of this invention.After calibration and storage of the pixel count number in data store62, controller 50 may perform offset compensation by first receiving andcounting the pixel signals reflected from the target retroreflector andthen adjusting this count according to the stored LOS offset to obtainan adjusted count from which the precise target hit location may bededuced in the manner described below in connection with FIGS. 12A-12D.

[0043] In an alternative embodiment of this invention that does notrequire a target retroreflector, the elements of calibration system 44represented by offset logic 54 are collocated at the target as shown inFIG. 5 instead of being located at the shooter as shown in FIG. 4. Theoffset logic 64 is coupled to an optical sensor 66 at target bulls-eye30 (FIGS. 1-3) for recovering the optical pixel signals arriving alonglaser beam axis 22. Optical sensor 66 may be alone or may cooperate withone or more other optical sensors in an optical sensor array 68 spanningthe target around bullseye 30, for example. A counter logic 70 and adecoder logic 72 operate similarly to logics 58 and 60 (FIG. 4) torecover pixel signal count numbers and selected pulse codes, which arereduced to a shooter LOS offset by the controller 74. Controller 74stores the shooter LOS offset in the data store 76 and causes the offsetsignal transmitter 78, embodied as a radio frequency (RF) or millimeterwave (MMW) transmitter, for example, to transmit an offset signal 80 tothe optional offset signal receiver 82 shown in FIG. 4, from where theshooter LOS offset is passed to controller 50. System 44 may includeeither offset logic 54 or offset signal receiver 82, or both, forexample, thereby permitting the shooter to recalibrate his sight-picturecompensation in the field during an exercise, if necessary.

[0044] In another alternative embodiment of this invention, anothersoldier may be equipped to wear the target portion of the ZSATcalibration system of this invention, including target bulls-eye 30(FIGS. 1 and 3). For example, FIG. 6 shows another soldier wearing avest 84 to which is fixed a target bulls-eye 86 including, for example,a retroreflector or an optical sensor. If bulls-eye 86 includes aretroreflector, vest 84 may passively cooperate with the sight-picturecalibration procedure performed by a distant ZSAT assembly.Alternatively, if bulls-eye 86 includes an optical sensor, vest 84 alsoincludes the signal processing electronics 88 for performing thefunctions discussed above in connection with FIG. 5, for example.Moreover, electronics 88 may include additional devices for recordingand reporting hits and misses, which are beyond the scope of thisdiscussion. This is a useful embodiment because the MILES 2000 trainingsystem known in the art, for example, includes vests and H-harnessesequipped to detect and report simulated small arms hits and missesduring training exercises. These vests may be easily adapted by addingfirmware to operate as discussed above in connection with FIG. 5, forexample.

[0045]FIG. 7 illustrates yet another alternative embodiment of thisinvention, where vest 84 is equipped with a sensor array 90, includingoptical sensor 86, for use in collecting transmitted optical pixels intwo dimensions in accordance with a precision hit/miss detection methodof this invention, which may be appreciated with reference to thefollowing discussion in connection with FIGS. 12A-12D.

[0046]FIG. 8 is a chart illustrating an exemplary two-dimensionaldynamic muzzle displacement signature 92 characterizing a weapon uponfiring a blank cartridge through a BFA affixed to the weapon muzzle asshown in FIGS. 1-3, for example. The inventors have advantageouslyobserved that a small arms weapon oscillates during the firing of ashot. The oscillation frequency and amplitude are determined by thetransfer of the breech mass forwards and backwards under the impulsiveforce of the cartridge detonation and subsequent gas expulsion from themuzzle, which may be equipped with a BFA. The impulse force istranslated into lateral motion by the resolved lateral force acting on alever arm formed between the breech mechanism and the shooter's forwardgrip. The inventors have observed that the oscillation frequency andamplitude are a reasonably invariant function of the weapon topology andmass.

[0047] In FIG. 8, dynamic muzzle displacement signature 92 representsseveral of the features noted by the inventors during repeatedexperimental measurements of a blank cartridge fired from a weaponequipped with a BFA fixed in a consistent disposition to the weaponmuzzle (FIGS. 1-3). Assuming a horizontal BFA gas port dispositiondirecting gas to the left, the first quarter cycle portion 94 of thesinusoidal oscillation is mainly from left to right, although a smallersinusoidal vertical oscillation may be noted. Displacement signature 92is shown beginning at the initial aimpoint 23 of ZSAT laser beam axis 22(FIGS. 1-3) and proceeding, for this example, to the right at about 0.2milliradians per millisecond for about 10 milliseconds. The vertical andhorizontal cycles continue, describing a path about the initial aimpoint23 substantially as shown. The first quarter-cycle portion 94 from 0-10milliseconds is useful for the LOS calibration system of this invention,as is now described.

[0048]FIG. 9 illustrates a two-dimensional dynamic muzzle displacementsignature 96 representing the AZ and EL angles of the firstquarter-cycle 94 (FIG. 8) for a blank cartridge fired from a weaponequipped with a BFA fixed in a predetermined disposition to the weaponmuzzle. The period of displacement signature 96 is about 10 millisecondsand the (AZ, EL, T) coordinates of the exemplary pixels shown in FIG. 9can be saved in a data store in a form that represents displacementsignature 96 corresponding to the predetermined BFA disposition on theweapon. Displacement signature 96 can be measured using, for example,high-speed video equipment and a laboratory fixture, for any combinationof small arms weapon, blank cartridge, and BFA disposition.

[0049] When triggering the weapon to fire a blank cartridge, the dynamicmuzzle displacement may be exploited to paint the target with a sequenceof optical pixels transmitted from ZSAT 44 (FIG. 4) in synchronizationwith the dynamic muzzle displacement rate. For example, ten pixelsexemplified by the pixel 97, are evenly distributed over signature 96,representing one pixel signal transmission every one millisecond aftertrigger pull. In this example, each pixel position would differ from theprevious pixel position by about 0.4 milliradians in AZ and perhaps 0.2milliradians or so in EL.

[0050]FIG. 10 is a chart illustrating another exemplary embodiment ofthe optical pixel sequence of this invention transmitted upon triggeringa weapon having dynamic muzzle displacement signature 96 (FIG. 9). Forexpository purposes, FIG. 10 shows only the horizontal AZ component 98of displacement signature 96 versus time T in milliseconds. In thisexample, the pixel signals are encoded as a sequence and spaced at 0.5millisecond intervals such that the AZ of each pixel differs from the AZof its neighbor by about 0.2 milliradians. Beginning at trigger pull(T=0), the first few hundred microseconds are reserved for theprojectile transit interval 100 and the next couple of milliseconds arereserved for the muzzle gas cloud dissipation interval 102, during whichperiods the optical signals are not usefully propagated. Muzzle gascloud dissipation interval 102 ends at about 2.5 milliseconds. Thesequence of optical pixel signals within the calibration interval 104includes, for example, sixteen pixels spaced at about 0.2 milliradians,beginning with the pixel 106 (encoded as P00) after the muzzle gas cloudhas dissipated (to avoid beam distortion effects) and ending with thepixel 108 (encoded as P15). Preferably, each optical pixel signal isencoded (P00, P15 for example) to permit pixel identification and topermit reordering or recoding of the pixel sequence to compensate forthe shooter LOS offset. However, the method of this invention is notnecessarily limited to an embodiment using sequential optical pixelencoding. FIG. 9 also demonstrates that, while the pixel sequence ininterval 104 is preferably evenly-spaced in AZ, it may not necessarilybe linearly spaced in time.

[0051]FIG. 11 is a block diagram of a flow chart illustrating theautomatic sight picture alignment method of this invention. At the firststep 116, the new shooter aligned the LOS with the target, which mayinclude a retroreflector or a sensor. The shooter then triggers theweapon to fire a blank cartridge through the BFA at step 118. Withinmilliseconds, the ZSAT sends a predetermined series of laser pulsesencoded as pixels to the target in step 120. In step 122, the pixelsilluminating the target are detected and counted, either at the targetby a sensor, for example, or at the shooter by means of targetretroreflections, for example. In the step 124, a pixel count is stored,at the shooter, for example, and used to modify the pixel encoding tocompensate for shooter sight-picture misalignment during later blankcartridge fire.

[0052] FIGS. 12A-12C are charts illustrating an exemplary embodiment ofthe method of this invention for deducing the horizontal component of ashooter LOS offset from the number and identity of thetarget-illuminating optical pixels. For expository purposes, the ELcomponent and the effects of projectile transit interval 100 and muzzlegas cloud dissipation interval 102 (FIG. 10) are ignored. FIG. 12A showslaser beam 22 centered at aimpoint 23 (AZ=0) on retroreflector 109,which coincides with the shooter LOS in these examples. The rate ofmuzzle displacement is assumed to be 0.4 milliradians per millisecond tothe right so the displacement signature will move the laser beam from(AZ=0) to the right by +1.6 milliradians in 4 milliseconds. Assumingthat two pixel signals are transmitted per millisecond, the 3.2milliradian laser beam moves off of retroreflector 109 after about 4milliseconds. With these assumptions, the first eight pixel signals incalibration interval 104 (FIG. 10) are reflected and the subsequentpixel signals are not. Eight pixels are reflected and detected and eightare not (assuming a 16-pixel sequence). With this exemplary arrangement,receiving the first half of the pixels signifies a zero LOS offset fromlaser beam axis 22 (the laser beam center). That is, a zero LOS offsetmeans that the shooter LOS and the ZSAT laser beam axis are coincidentat the target distance.

[0053]FIG. 12B shows aimpoint 23 (AZ=0) of laser beam axis 22 offset by1.6 milliradians to the right of the shooter LOS at retroreflector 109,representing a shooter LOS error of +1.6 milliradians. Using theparameters discussed above in connection with FIG. 12A, even the firstpixel signal does not illuminate retroreflector 109 because the positive(right) offset error is not less than half of the 3.2 milliradian laserbeam width. Accordingly, any errors of +1.6 milliradians or more cannotbe calibrated without broadening the ZSAT laser beam width. Any less ofa right offset is detected as one or more pixel signal reflections. Inthese examples, the LOS offset error can be calibrated to within 0.2milliradians, which is only 6.25% of the 3.2 milliradian ZSAT laser beamwidth. This vernier feature of this invention for the first time allowsthe offset calibration precision to substantially exceed the ZSAT laserbeam width.

[0054]FIG. 12C shows the laser beam aimpoint 23 (AZ=0) offset by 1.6milliradians to the left of retroreflector 109, representing a shooterLOS error of −1.6 milliradians. Using the parameters discussed above inconnection with FIG. 16A, all sixteen pixel signals including the lastone will illuminate retroreflector 109 because the negative offset erroris not less than half of the 3.2 milliradian laser beam width.Accordingly, any negative errors of −1.6 milliradians or more cannot becalibrated without broadening the ZSAT laser beam width. Any less of aleft offset is detected as one or more fewer pixel signal reflections.

[0055] It may be readily appreciated from this description of FIGS.12A-12C that any LOS offset in the interval between [−1.6, +1.6]milliradians may be calibrated and stored as a pixel signal count forlater use in compensating for the shooter LOS offset. FIG. 12D showsthat this method of this invention may also be used to precisely refinethe location of “hit” and “kill” points on a target including an arrayof sensors such as is shown in FIG. 7. This “precision” hit/kill pointresolution is refined far beyond the precision possible with a simpledetection of a 3.2 milliradian laser beam. Consider the retroreflectorarray in FIG. 12D made up of the sensors 110A-B, which are spaced apartby 4 milliradians (about 4 cm at 25 m, or about 50 cm at 300 m).Assuming that the shooter LOS aimpoint 23 (represented by pixel P00) ispositioned at about −2.8 milliradians to the left of sensor 10B andabout +1.2 milliradians to the right of sensor 11A. With the assumptionsdescribed above in connection with FIG. 12A, sensor 110A detects pixelsignals (P00-P01) and misses the others (P02-P15). Sensor 110B missespixel signals (P00-P06) and detects pixel signals (P07-P15).Accordingly, the target system can precisely locate aimpoint 23 at −0.4milliradians on the scale shown in FIG. 12D. This precision is within0.2 milliradians (5 mm at 25 m or 6 cm at 300 m) even though a 3.2milliradian laser beam is used for targeting. It may be readilyappreciated that the described method may be extended to one- andtwo-dimensional arrays of multiple sensors. This same precision is alsopossible using the method of this invention with a single target sensoror retroreflector (such as shown in FIGS. 12A-C) located within 1.6milliradians of the target kill point.

[0056] Practitioners in the art can readily appreciate that other beamwidths, pixel sequences, and target characteristics may be selected toadapt the calibrating method of this invention to different weapon andBFA characteristics. For example, by coding the optical pixel sequencein interval 104 (FIG. 10) to identify the vertical and horizontal LOSoffsets recorded for truncated dynamic muzzle displacement signature 96,a two-dimensional LOS offset may be deduced from the number and codingof the pixels detected at bulls-eye 30. As another example, duringcalibration, a useful pixel computation method may be advantageouslyemployed in lieu of the simple pixel counting technique described aboveto determine a calibration offset value that may be then used withanother computation method to correct shooter LOS offset duringexercises.

[0057] When the misalignment of laser beam axis aimpoint 23 with shooterLOS 36 (FIG. 3) is calibrated and stored, the shooter LOS offsetcompensation remains in data store 62 (FIG. 4) until the ZSAT isrecalibrated by another shooter. In use, shooter sight picturecompensation may be achieved from the stored LOS offset in any ofseveral useful ways. For example, an integer number N related to thestored pixel offset calibration results may be subtracted from eachpixel code detected during interval 104 by vest 84, which is worn by thetarget during the training shot. Thus, optical pixel (P00-N) isrecognized as the “kill” signal by vest 84 instead of first pixel signalP00, which is known to be misaligned. Alternatively, the vest softwaremay be adapted to decode the offset pixel code (N) and/or GlobalPositioning System (GPS) data received from the ZSAT. Using this offsetpixel code and the GPS coordinates, the vest may conduct a hit/missassessment based on the pixels signals detected at the bulls-eye.

[0058] Following sight picture calibration according to any method ofthis invention, a standard MILES 2000 vest and a standard MILES SATmodified to delay transmission of the standard MILES 2000 SAT pulsecodes by a time interval representing the stored LOS offset. That is, byadding the sight-picture calibration software of this invention to theMILES SAT and adding a retroreflector to the MILES 2000 vest, merelydelaying transmission of the standard MILES 2000 SAT beam codesaccording to the stored LOS offset compensates for the shooter sightpicture error without resorting to a live-fire target facility.

[0059] Clearly, other embodiments and modifications of this inventionmay occur readily to those of ordinary skill in the art in view of theseteachings. Therefore, this invention is to be limited only by thefollowing claims, which include all such embodiments and modificationswhen viewed in conjunction with the above specification and accompanyingdrawing.

We claim:
 1. In a weapon training system for simulating the use of aweapon against a target by a shooter having a line-of-sight (LOS) to thetarget, the system including a retroreflector adapted to be secured tothe target for reflecting an incident optical signal back along the lineof incidence, and a small-arms transmitter (SAT) assembly having a laserbeam axis and adapted to be secured to the weapon, a method forcalibrating a misalignment of the laser beam axis with the shooter LOS,comprising the steps of: (a) aligning the shooter LOS with theretroreflector; (b) triggering the weapon to fire a blank cartridge; (c)transmitting a sequence of optical pixel signals along the laser beamaxis responsive to the weapon triggering step (b); (d) detecting one ormore optical pixel signals reflected from the retroreflector; and (e)storing a shooter LOS offset corresponding to the reflected opticalpixel signals detected.
 2. The calibrating method of claim 1 furthercomprising the step of: (c.1) encoding each of the optical pixel signalsas a beam number.
 3. The calibrating method of claim 2 wherein theweapon training system includes a blank fire adaptor (BFA) adapted to besecured to the weapon, further comprising the steps of: (a.1) securingthe BFA to the weapon in a predetermined disposition; and (c.2)configuring the sequence of optical pixel signals according to asignature corresponding to the predetermined BFA disposition.
 4. Thecalibrating method of claim 1 further comprising the steps of: (f)repeating the steps (a) through (d); and (g) revising the shooter LOSoffset according to the reflected optical pixel signals detected.
 5. Ina weapon training system for simulating the use of a weapon against atarget by a shooter having a line-of-sight (LOS) to the target, thesystem including a first optical detector adapted to be secured to thetarget for receiving an incident optical signal, and a small-armstransmitter (SAT) assembly having a laser beam axis and adapted to besecured to the weapon, a method for calibrating a misalignment of thelaser beam axis with the shooter LOS, comprising the steps of: (a)aligning the shooter LOS with the optical detector; (b) triggering theweapon to fire a blank cartridge; (c) transmitting a sequence of opticalpixel signals along the laser beam axis responsive to the triggeringstep (b); (d) detecting one or more optical pixel signals received atthe first optical detector; and (e) storing a shooter LOS offsetcorresponding to the optical pixel signals detected.
 6. The calibratingmethod of claim 5 further comprising the step of: (c.1) encoding each ofthe optical pixel signals as a beam number.
 7. The calibrating method ofclaim 6 wherein the weapon training system includes a second opticaldetector adapted to be secured to the target for receiving an incidentoptical signal and for cooperating with the first optical detector toform an optical detector array, the method further comprising the stepsof: (d.1) detecting the optical pixel signals received at the secondoptical detector; and (e.1) storing a two-dimensional shooter LOS offsetcorresponding to the optical pixel signals detected
 8. The calibratingmethod of claim 7 further comprising the step of: (e.2) transmitting tothe SAT assembly a signal representing the two-dimensional shooter LOSoffset.
 9. The calibrating method of claim 6 wherein the weapon trainingsystem includes a blank fire adaptor (BFA) adapted to be secured to theweapon, further comprising the steps of: (a.1) securing the BFA to theweapon in a disposition; and (c.2) configuring the sequence of opticalpixel signals according to a signature corresponding to thepredetermined BFA disposition.
 10. The calibrating method of claim 5further comprising the steps of: (f) repeating the steps (a) through(d); and (g) revising the shooter LOS offset according to the reflectedoptical pixel signals detected.
 11. The calibrating method of claim 5further comprising the steps of: (e.1) transmitting to the SAT assemblya signal representing the shooter LOS offset.
 12. A weapon trainingsystem for simulating the use of a weapon against a target by a shooterhaving a line-of-sight (LOS) to the target, the system comprising: aretroreflector adapted to be secured to the target for reflecting anincident optical signal back along the line of incidence; and asmall-arms transmitter (SAT) assembly having a laser beam axis andadapted to be secured to the weapon, including an optical transmitter,an optical detector for receiving optical pixel signals from theretroreflector, and a sight-picture compensator for calibrating themisalignment of the laser beam axis with the shooter LOS, including acontroller coupled to the optical transmitter for producing an opticalpixel signal sequence responsive to the triggering of the weapon, and adata store coupled to the optical detector for storing a shooter LOSoffset corresponding to the reflected optical pixel signals detected.13. The weapon training system of claim 12 further comprising: anencoder coupled to the controller for encoding each of the optical pixelsignals as a beam number.
 14. The weapon training system of claim 13wherein the encoder is coupled to the data store and includes means forencoding each of the sequence of optical pixel signals according to theshooter LOS offset.
 15. The weapon training system of claim 13 furthercomprising: a blank fire adaptor (BFA) adapted to be secured to theweapon, wherein the sequence of optical pixel signals is encodedaccording to a signature corresponding to a predetermined BFAdisposition on the weapon.
 16. The weapon training system of claim 12wherein the optical transmitter comprises: an infrared laser adapted togenerate an optical signal in the range from generally 800 nanometers togenerally 10,600 nanometers.
 17. A weapon training system for simulatingthe use of a weapon against a target by a shooter having a line-of-sight(LOS) to the target, the system comprising: a first optical detectoradapted to be secured to the target for receiving an incident opticalpixel signal; a small-arms transmitter (SAT) assembly having a laserbeam axis and adapted to be secured to the weapon, including an opticaltransmitter, and a sight-picture compensator for offsetting themisalignment of the laser beam axis with the shooter LOS to the target,including a controller coupled to the optical transmitter for producingan optical pixel signal sequence responsive to the triggering of theweapon, and a data store coupled to the controller for storing a shooterLOS offset corresponding to the optical pixel signals detected.
 18. Theweapon training system of claim 17 further comprising: an encodercoupled to the controller for encoding each of the optical pixel signalsas a beam number.
 19. The weapon training system of claim 18 furthercomprising: a blank fire adaptor (BFA) adapted to be secured to theweapon, wherein the sequence of optical pixel signals is encodedaccording to a signature corresponding to a predetermined BFAdisposition on the weapon.
 20. The weapon training system of claim 17further comprising: a signal transmitter coupled to the optical detectorfor transmitting an offset signal representing the shooter LOS offset;and a signal receiver coupled to the SAT assembly for receiving theoffset signal
 21. The weapon training system of claim 20 wherein theencoder is coupled to the signal receiver and includes means forencoding each of the sequence of optical pixel signals according to theshooter LOS offset.
 22. The weapon training system of claim 17 whereinthe optical transmitter comprises: an infrared laser adapted to generatean optical signal in the range from generally 800 nanometers togenerally 10,600 nanometers.
 23. The weapon training system of claim 17further comprising: a second optical detector adapted to be secured tothe target for receiving an incident optical signal and for cooperatingwith the first optical detector to form an optical detector array; andmeans for storing in the data store a two-dimensional shooter LOS offsetcorresponding to a plurality of optical pixel signals.
 24. A small-armstransmitter (SAT) assembly having a laser beam axis and adapted to besecured to a weapon for use in a weapon training system for simulatingthe use of the weapon against a target by a shooter having aline-of-sight (LOS) to the target, including a retroreflector secured tothe target for reflecting an incident optical signal back along the lineof incidence, the SAT assembly comprising: an optical transmitter; anoptical detector for receiving optical pixel signals from theretroreflector; and a sight-picture compensator for calibrating themisalignment of the laser beam axis with the shooter LOS, including acontroller coupled to the optical transmitter for producing an opticalpixel signal sequence responsive to the triggering of the weapon, and adata store for storing a shooter LOS offset corresponding to thereflected optical pixel signals detected.
 25. The SAT assembly of claim24 further comprising: an encoder coupled to the controller for encodingeach of the optical pixel signals as a beam number.
 26. The SAT assemblyof claim 25 wherein the encoder is coupled to the data store andincludes means for encoding each of the sequence of optical pixelsignals according to the shooter LOS offset.
 27. The SAT assembly ofclaim 25 wherein a blank fire adaptor (BFA) is secured to the weapon ina predetermined disposition, the SAT assembly further comprising: meansfor encoding the sequence of optical pixel signals according to asignature corresponding to the predetermined BFA disposition on theweapon.
 28. The SAT assembly of claim 24 wherein the optical transmittercomprises: an infrared laser adapted to generate an optical signal inthe range from generally 800 nanometers to generally 10,600 nanometers.29. A small-arms transmitter (SAT) assembly having a laser beam axis andadapted to be secured to a weapon for use in a weapon training systemfor simulating the use of the weapon against a target by a shooterhaving a line-of-sight (LOS) to the target, including a first opticaldetector adapted to be secured to the target for receiving an incidentoptical signal, the SAT assembly comprising: an optical transmitter; anda sight-picture compensator for offsetting the misalignment of the laserbeam axis with the shooter LOS to the target, including a controllercoupled to the optical transmitter for producing an optical pixel signalsequence responsive to the triggering of the weapon, and a data storefor storing a shooter LOS offset corresponding to the optical pixelsignals detected.
 30. The SAT assembly of claim 29 further comprising:an encoder coupled to the controller for encoding each of the opticalpixel signals as a beam number.
 31. The SAT assembly of claim 30 whereina signal transmitter is coupled to the first counter for transmitting anoffset signal representing the shooter LOS offset, the SAT assemblyfurther comprising: a signal receiver coupled to the data store forreceiving the offset signal.
 32. The SAT assembly of claim 31 whereinthe encoder is coupled to the signal receiver and includes means forencoding each of the sequence of optical pixel signals according to theshooter LOS offset.
 33. The SAT assembly of claim 30 wherein a blankfire adaptor (BFA) is secured to the weapon in a predetermineddisposition, the SAT assembly further comprising: means for encoding thesequence of optical pixel signals according to a signature correspondingto the predetermined BFA disposition on the weapon.
 34. The SAT assemblyof claim 29 wherein the optical transmitter comprises: an infrared laseradapted to generate an optical signal in the range from generally 800nanometers to generally 10,600 nanometers.
 35. The SAT assembly of claim29 wherein a second optical detector is secured to the target forreceiving an incident optical signal and for cooperating with the firstoptical detector to form an optical detector array, the SAT assemblyfurther comprising: means for storing in the data store atwo-dimensional shooter LOS offset corresponding to a plurality ofoptical pixel signals.
 36. The SAT assembly of claim 29 a signaltransmitter is coupled to the data store for transmitting an offsetsignal representing the shooter LOS offset, the SAT assembly furthercomprising: a signal receiver for receiving the offset signal.
 37. In aweapon training system for simulating the use of a weapon against atarget by a shooter having a line-of-sight (LOS) to the target, thesystem including a retroreflector adapted to be secured to the targetfor reflecting an incident optical signal back along the line ofincidence, and a small-arms transmitter (SAT) assembly having a laserbeam axis and adapted to be secured to the weapon, a method forprecisely locating a simulated hit point on the target, comprising thesteps of: (a) aligning the shooter LOS with the retroreflector; (b)triggering the weapon to fire a blank cartridge; (c) transmitting asequence of optical pixel signals along the laser beam axis responsiveto the weapon triggering step (b); (d) detecting one or more opticalpixel signals reflected from the retroreflector; and (e) determining thesimulated hit point corresponding to the reflected optical pixel signalsdetected.
 38. The calibrating method of claim 37 further comprising thestep of: (c.1) encoding each of the optical pixel signals as a beamnumber.
 39. A weapon training system for simulating the use of a weaponagainst a target by a shooter having a line-of-sight (LOS) to thetarget, the system comprising: a retroreflector adapted to be secured tothe target for reflecting an incident optical signal back along the lineof incidence; and a small-arms transmitter (SAT) assembly having a laserbeam axis and adapted to be secured to the weapon, including an opticaltransmitter, an optical detector for receiving an optical pixel signalfrom the retroreflector, and a precision hit-point localizer forprecisely locating a simulated hit point on the target, including acontroller coupled to the optical transmitter for producing an opticalpixel signal sequence responsive to the triggering of the weapon, and alogic coupled to the optical detector for determining the simulated hitpoint corresponding to the reflected optical pixel signals detected. 40.The weapon training system of claim 39 further comprising: an encodercoupled to the controller for encoding each of the optical pixel signalsas a beam number.
 41. In a weapon training system for simulating the useof a weapon against a target by a shooter having a line-of-sight (LOS)to the target, the system including a first optical detector adapted tobe secured to the target for receiving an incident optical signal, and asmall-arms transmitter (SAT) assembly having a laser beam axis andadapted to be secured to the weapon, a method for precisely locating asimulated hit point on the target, comprising the steps of: (a) aligningthe shooter LOS with the optical detector; (b) triggering the weapon tofire a blank cartridge; (c) transmitting a sequence of optical pixelsignals along the laser beam axis responsive to the triggering step (b);(d) detecting one or more optical pixel signals received at the firstoptical detector; and (e) determining the simulated hit pointcorresponding to the number of optical pixel signals detected.
 42. Thecalibrating method of claim 41 further comprising the step of: (c.1)encoding each of the optical pixel signals as a beam number.
 43. Thecalibrating method of claim 41 wherein the weapon training systemincludes a second optical detector adapted to be secured to the targetfor receiving an incident optical signal and for cooperating with thefirst optical detector to form an optical detector array, the methodfurther comprising the steps of: (d.1) detecting one or more opticalpixel signals received at the second optical detector; and (e.1)determining the simulated hit point corresponding to a plurality of theoptical pixel signals detected.
 44. A weapon training system forsimulating the use of a weapon against a target by a shooter having aline-of-sight (LOS) to the target, the system comprising: a firstoptical detector adapted to be secured to the target for receiving anincident optical signal; and a small-arms transmitter (SAT) assemblyhaving a laser beam axis and adapted to be secured to the weapon,including an optical transmitter, and a sight-picture compensator foroffsetting the misalignment of the laser beam axis with the shooter LOSto the target, including a controller coupled to the optical transmitterfor producing a optical pixel signal sequence responsive to thetriggering of the weapon, and a data store coupled to the controller forstoring a shooter LOS offset corresponding to the optical pixel signalsdetected.
 45. The weapon training system of claim 44 further comprising:an encoder coupled to the controller for encoding each of the opticalpixel signals as a beam number.
 46. The weapon training system of claim44 further comprising: a second optical detector adapted to be securedto the target for receiving an incident optical signal and forcooperating with the first optical detector to form an optical detectorarray; and means for determining the simulated hit point correspondingto a plurality of the optical pixel signal count detected.
 47. In aMultiple Integrated Laser Engagement System (MIES) system for simulatingthe use of a weapon against a target by a shooter having a line-of-sight(LOS) to the target, the system including a MILES target vest and asmall-arms transmitter (SAT) assembly adapted to be secured to theweapon and having a laser beam axis and means for storing a shooter LOSoffset, a method for compensating a misalignment of the laser beam axiswith the shooter LOS, comprising the steps of: (a) aligning the shooterLOS with the target vest; (b) triggering the weapon; (c) transmitting asequence of MILES optical codes along the laser beam axis responsive tothe weapon triggering step (b), wherein each MILES optical code isdelayed with respect to the triggering step (b) according to the storedshooter LOS offset.